On a late Oregon summer morning two weeks from tomorrow, around brunch-time, the shadow of the new moon will slide across the coast and a strange twilight will fall throughout the upper Pacific Northwest. It’s too soon to try and guess what the weather will be like. But the Great Eclipse of 2017 will cut a shadowy swath from the great northwest to the eastern seaboard of the Carolinas, and no doubt there will be some clear skies all along its route. It’ll be a grand sight in the sky! But back here on Earth, there may be panic and chaos, and most of it won’t be caused by ancient superstition and deep seated fears engraved in our hind-brain.
The last total eclipse in the US barely touched the northwest corner in 1979. The last time we had a coast-to-coast tour of daytime darkness was June 8, 1918, when the US was still fighting World War 1. Which means this will be the first such spectacle since the widespread availability of cars, planes, and interstate highways. A hundred million people live within a few hours drive of the path of totality and weather will be an unknown right up until a few days before the big day, so there will probably be chaos in many places alright:
No one likes an overflowing toilet. But figuring out how many port-a-potties to rent for a once-in-a-lifetime event is challenging. Patti Carter is chair of the solar eclipse task force for Chester, Illinois, a town of 8,500 that’s about 50 miles south of St. Louis. She said her town started with an estimate of 10,000 visitors but after meetings with the county emergency management agency is now planning for 25,000 people to show up at its viewing areas. More people will obviously need more toilets, and the number required rises still further the longer visitors stay at an event site.
If you’re lucky enough to make it to eclipse holy land, be ready for traffic snarls lasting for hours on major interstates in the middle of nowhere going both ways on both sides of the path. But it will probably be worth it. Because you’ll get to see the Earth and sky lit by the sun’s glowing, flickering corona. That’s a phenomenon rarely seen—the sun is so bright that the corona is usually invisible. On Monday, Aug 21, it will be plainly evidence for all to see and enjoy. NASA and sky gazers will take maximum advantage of the opportunity to resolve some mysteries of science.
One of the biggest mysteries is why the visible surface of the sun comes in at a warm 5,000—10,000 F, but the temperature of the sun’s corona is hundreds of times greater. So hot it’s a plasma, a fourth state of matter, where the usual atomic family of protons and electrons are broken up.
The plasma is super-heated, to a toasty couple of million degrees, and extends out from the sun for millions of miles. It slowly fades away and fuels the particulate portion of the solar wind. A gale of hydrogen and helium nuclei that blows into interstellar space for light-years. By some accounts, the bow shock, the boundary where the sizzling hot solar sleet gives way to the usual cold vacuum between stars in the Milky Way, is the official edge of our solar system. An important question in solar astronomy and climate science concerns how much of the sun’s total heat output, especially that which is intercepted by Earth, comes from that corona.
Another interesting thing to figure out is what role the corona plays in producing enormous loops of fiery starstuff, some of which give rise to giant streamers of plasma, flares that reach out from the sun and lick the surface of nearby planets like a flame-thrower. Some of these displays are beautiful, while some of the worst could also be destructive.
That was in 2012 and that single loop was bigger than worlds. Sometimes, those events or others like them break away from the sun at a thousand miles per second and head out towards planets and moons. If one were to strike Earth, well, we can’t say for sure what might happen, because we haven’t experienced a really big one hitting close to home in 150 years. The last time that happened was way back in 1859, when a coronal mass ejection hit our planet dead on. You can read more about it here, but the short version is, if one like it happened today, it could fry our delicate intertoobz infrastructure, destroy the protective ozone layer thus laying waste to crops and phyto-plankton, and crash the entire global economy in the process.
The corona is a magical place that was only revealed only during total solar eclipses throughout history. It’s only in the last few decades that we even understood it existed, let alone its importance. On August 21, it will become a living laboratory of churning magnetic chaos visible to anyone in the path of totality lucky to have a clear view—and with eyes properly protected.
Here are some links on how to observe the eclipse safely along with some info on times and places and Astronomy’s eclipse viewing widget. No doubt we’ll see your pictures and read your observations right here on Daily Kos. Because statistically, thousands of you will be in the path of totality.